Patent GB-724039-A (GB)
Title: Improvements in or relating to water depth recorder apparatus
Inventor: RYMES WILLIAM HENRY
IPC: G01S1/72
Filed: 1952-09-26
Abstract: 724,039. Echo-sounding apparatus. RAYTHEON MANUFACTURING CO. Sept. 26, 1952, No. 24232/52. Class 118 (2) [Also in Group XIX] A pulse echo-sounder for recording the submerged depth of a submarine and the depth of water below the submarine comprises an upwardly. directed common transmitting and receiving transducer 42 mounted on the deck of the submarine and a downwardly directed common transducer 41 mounted on the keel, the two transducers being connected to a common pulse exciter 43 and to respective recording means which traverse a record-strip 10 in opposite directions from a common origin in synchronism with the pulse transmission, the transverse position of the origin being adjusted automatically by a hydrostatic depth gauge 50 and the record strip being moved longitudinally at a speed proportional to that of the submarine so that the two superimposed traces 77, Fig. 2 produced by the direct pulses. indicate the depth of the submarine and the traces 75, 76 produced by the surface and bottom echoes indicate respectively the surface and bottom conditions. In a modification the origins of the two recording means are separated transversely by an amount proportional to the vertical separation of the two transducers thus producing two parallel direct traces, Fig. 3 (not shown). The operating frequencies of the two transducers may be the same or different and when the submarine is on the surface a dummy load 46 is switched to replace the deck transducer 42 by means of a pressure-operated switch 83. The invention is described as applied to an electrochemical recorder comprising a rotating roller 12 with two oppositely-wound single-turn helical blades 17, 18 such that the two points of contact between the blades and the record strip move outwards across the strip in opposite directions but alternatively a recorder with moving styli may be employed. The record paper 10 is fed from a feed roller 11 'to a take-up roller 13 driven by a motor 14, the rollers and motor being mounted on a bed plate 5. The paper passes over a printing roller 12, journaled tor rotation, against the movement of the paper 10 in a carriage 26 movable transversely with respect to the paper 10. The roller has two single turn helical contact blades 17, 18 wound in opposite directions and starting at or near the same point 49. Printer bars 21, 22 are connected by a strip 23 of insulating material and are mounted between supports 29, 30 on carriage 26 and pressed by springs 33, 34 against the blades 17, 18. The paper is marked when electric impulses are applied between bars 21, 22 and blades 17, 18 respectively. The exciter 43 is keyed by a switch 44 actuated by a cam 45 on the shaft of the printing roller 12 when the point 49 is in contact with the paper 10. The transducers receive the reflected pulses, the signals being amplified by a two-channel amplifier 48 and fed along lines 35, 36 to the printing bars 21, 22. The depth gauge 50 controls the position of the carriage 26 through a servomotor system so that the distance of the point 49 from the edge of the paper corresponds to the depth of the submarine. The pulses are sent out when the point 49 is in contact with the paper and marks are made on the paper by the exciting current at a point indicating the depth of the submarine. As the roller 12 is rotated at constant speed by a motor 19, the marks made when the reflected pulses are picked up are spaced from the first-mentioned marks in such a way as to indicate the depth of water above and below the submarine. When the distance between the transducers 41, 42 is to be taken into account, the printing bars 21, 22 are moved apart slightly, the connections to the supports 29, 30 and the strip 23 being by screws and slots for this purpose. The initial impulses then mark the paper at two points separated by a distance corresponding to the distance between the transducers. In either case, the vertical course of the submarine is reproduced as a line between two lines representing the surface and the sea-bed respectively. U.S.A. Specification 2,250,509 is referred to.